What type of conduit body has a threaded straight hub on each end?

A coupling is a type of conduit body that has a threaded straight hub on each end, precisely designed to connect two lengths of conduit. This threaded design allows for secure and reliable attachment, ensuring that the electrical pathways remain uninterrupted and protected from environmental factors. Couplings are typically used in situations where two conduit runs need to be joined in a straight line.

While a box serves more as a junction point for multiple conduit runs and is equipped with openings to accommodate wires, and an elbow allows for changes in direction of the conduit run, a coupling is specifically focused on the direct connection aspect. The term "conduit body" is a broader category that encompasses various forms, including couplings, boxes, and elbows, but does not specifically describe the connector feature that couplings offer. Hence, coupling is the precise answer to this question.